A. Michaut et al., Short-term changes in the series elastic component after an acute eccentric exercise of the elbow flexors, EUR J A PHY, 84(6), 2001, pp. 569-574
We have studied the effect of a unique eccentric exercise session on the se
ries elastic component (SEC) properties of human elbow flexors. Ten active
females performed five sets of ten maximal eccentric contractions on an iso
kinetic ergometer. Maximal isometric (MVC) torque, and the corresponding my
oelectrical activity (RMS) of the biceps brachii and the triceps brachii mu
scles were recorded before. immediately after, 48 h after, and 1 week after
the exercise session. SEC compliance was also measured, using the in situ
quick-release technique. Maximal eccentric torque declined significantly am
ong the five sets of the exercise session (P <0.01). The exercise session i
nduced a significant decrease of the MVC over the post-exercise 48-h period
. MVC returned to its control value 1 week after the exercise session. The
neuromuscular efficiency calculated from the MVC torque:RMS ratio did not c
hange throughout the experimental period, suggesting an optimisation of the
neural drive to muscle force production capacity. The compliance values in
creased when force values decreased. but the slope of the relationship betw
een both compliance and force logarithmic values was not significantly modi
fied by the experimental procedure, indicating that the intrinsic propertie
s of the SEC were not affected by the eccentric exercise session. The contr
actility-elasticity coupling was also maintained at a constant level during
the recovery period. In other words, after an acute eccentric exercise, th
e evolution of SEC compliance was closely linked to force changes.